Case Report Highlights Need for More Awareness of Different Porphyria Subtypes Among Doctors
A case involving a patient with erythropoietic protoporphyria (EPP) accompanied by liver damage highlights the need for increased awareness of porphyria among doctors making diagnoses, a case study reports.
The case study, “Diagnosis of erythropoietic protoporphyria with severe liver injury: A case report,” was published in World Journal of Gastroenterology.
Porphyria refers to a number of genetic disorders that interfere with the production of porphyrin. This ultimately makes it harder for the body to produce heme, which is needed for the transportation of oxygen in the blood. EPP is a specific type of porphyria that is most commonly caused by mutations in the FECH gene.
Porphyria can also lead to liver damage — but this is relatively rare in EPP, affecting only 1 in 10 patients with this already rare disease.
The report details the case of a 26-year-old man who was admitted to the hospital with a lifelong history of sun-induced skin inflammation. He had been diagnosed with abnormal liver function three years previously due to jaundice (yellow skin).
A month before being admitted, after drinking beer, some of these symptoms worsened, and the patient rapidly lost weight.
Researchers employed a variety of tests to rule out possibilities and reach a definitive diagnosis. They tested for liver-damaging viruses such as hepatitis for autoimmune activity that could damage the liver, and for a host of specific conditions.
Liver damage due to alcohol or pesticides — which the patient used in his job — was also considered as a possibility, but these didn’t explain the patient’s skin lesions.
Ultimately, the investigators arrived at the likely diagnosis of EPP based on the results of a blood smear and a liver biopsy.
They then conducted genetic sequencing tests of the patient, as well as some of his relatives, to identify the genetic change responsible. The patient was found to have two mutated copies of the FECH gene, confirming the diagnosis of EPP. The patient’s parents each had one mutant copy and one healthy copy, so they didn’t develop disease symptoms but still passed on the mutated genes.
Interestingly, the mutation inherited from the patient’s mother — called c.32_35dupCCCT (p.Arg13fs) — hasn’t been previously reported as an EPP-causing mutation.
Overall, the investigators used this case to highlight the need for increased awareness of porphyria to avoid missed or delayed diagnoses such as this. They note that EPP may be particularly hard to diagnose because, while many types of porphyria lead to changes that can be detected in urine samples, EPP — and a few other types such as tricarboxylic porphyria and hereditary fecal porphyria — doesn’t.
“The diagnosis of porphyria cannot be ruled out by negative urine porphyrin,” they write, adding that “porphyria should be considered in patients with the main manifestations of abnormal liver function accompanied by skin damage.”